VI Mode

Introduction

Kate’s VI mode is a project to bring Vim-like, modal editing to the Kate text editor and by extension to other KDE programs who share the same editor component. The project started as a Google Summer of Code project in 2008 – where all the basic functionality was written. I have continued to maintain and further develop this code and the number of missing features from Vim are slowly decreasing. Most Vim users will already be productive in Kate’s VI mode. A list of what’s missing is found at the bottom of the page.

This page is meant to be an updated overview of this work.

To enable the VI input mode, go toSettings → Configure Kate… → Editing → VI Input Mode.
It can also be toggled with the “VI Input Mode” setting in the “Edit” menu. (The default shortcut key is Meta+Ctrl+V – where Meta usually is the Windows key).

Goals

The goal of the VI mode is not to be a complete replacement for Vim and support all Vim’s features. Its aim is to make the “Vim way” of text editing – and the Vim habits learned – available for programs using the Kate text editor as their internal editor. These programs include

The Kate Text editor

KWrite – KDE’s simple text editor

KDevelop – An advanced IDE for many programming languages

Kile – A LaTeX editor

The VI mode aims integrate nicely with the programs and deviate from Vim’s behaviour where it makes sense. For example, :w will open a save dialogue in Kate’s VI mode.

Incompatibilities with Vim

There are only a few features of Kate’s VI mode which are incompatible with Vim (not counting things missing). They are listed below together with the respective reasons.

Kate: U and ctrl+r is redoVim: ctrl+r is normal redo, U is used to undo all latest changes on one line
The reason for having U act as redo in Kate’s VI mode is that the shortcut ctrl+r by default is taken by Kate’s replace function (search and replace). By default, the VI mode won’t override Kate’s shortcuts (this can be configured in Settings → Configure Kate… → Editing → Vi Input Mode), therefore a redo-action needs to be available as a “regular” key press, too. Besides, the behaviour of the U command in Vim doesn’t map well to Kate’s internal undo system, so it would be non-trivial to support anyway.

Kate: :print shows the ‘print’ dialogueVim: :print prints the lines of the given range like its grandfather ed
Commands like :print are available not only in the VI mode but for users using “regular” Kate, too – I have therefore chosen to let the :print command open the print dialogue – following the principle of least surprise instead of mimicking Vim’s behaviour.

Kate: ‘Y’ yanks to end of line.Vim: ‘Y’ yanks whole line, just like ‘yy’.
VI’s behaviour for the ‘Y’ command is in practice a bug; For both change and delete commands, ‘cc’/’dd’ will do its action on the current line and ‘C’/’D’ will work from the cursor column to the end of the line. However, both ‘yy’ and ‘Y’ yanks the current line.In Kate’s VI Mode ‘Y’ will yank to the end of the line. This is described as “more logical” in the Vim documentation.

Kate: :map alters the selected lines of the document using the provided Javascript expression.Vim: :map adds the provided mapping to Normal and Visual modes.
The “map” command was already reserved by Kate; in 4.12+, you can use a combination of :nmap and :vmap to replace it.

Supported Commands

Supported normal/visual mode commands

a

Enter Insert Mode and append

A

Enter Insert Mode and append to EOL

i

Enter Insert Mode

I

Insert before first non-blank char in line

v

Enter Visual Mode

V

Enter Visual Line Mode

<c-v>

Enter Visual Block Mode

gv

Re-select Visual

o

Open new line under

O

Open new line over

J

Join lines

c

Change

C

Change to EOL

cc

Change line

s

Substitute char

S

Substitute line

dd

Delete line

d

Delete

D

Delete to EOL

x

Delete char

X

Delete char backward

gu

Make lowercase

guu

Make lowercase line

gU

Make uppercase

gUU

Make uppercase line

y

Yank

yy

Yank line

Y

Yank to EOL

p

Paste

P

Paste before

r.

Replace character

R

Enter replace mode

:

Switch to command line

/

Search

u

Undo

<c-r>

Redo

U

Redo

m.

Set mark

>>

Indent line

<<

Unindent line

>

Indent lines

<

Unindent lines

<c-f>

Scroll page down

<pagedown>

Scroll page down

<c-b>

Scroll page up

<pageup>

Scroll page up

<c-u>

Scroll half page up

<c-d>

Scroll half page down

zz

Centre view on cursor

ga

Print character code

.

Repeat last change

==

Align line

=

Align lines

~

Change case

<c-a>

Add to number

<c-x>

Subtract from number

<c-o>

Go to prev jump

<c-i>

Go to next jump

<c-w>h

Switch to left view

<c-w><c-h>

Switch to left view

<c-w><left>

Switch to left view

<c-w>j

Switch to down view

<c-w><c-j>

Switch to down view

<c-w><down>

Switch to down view

<c-w>k

Switch to up view

<c-w><c-k>

Switch to up view

<c-w><up>

Switch to up view

<c-w>l

Switch to right view

<c-w><c-l>

Switch to right view

<c-w><right>

Switch to right view

<c-w>w

Switch to next view

<c-w><c-w>

Switch to next view

<c-w>s

Split horizontally

<c-w>S

Split horizontally

<c-w><c-s>

Split horizontally

<c-w>v

Split vertically

<c-w><c-v>

Split vertically

gt

Switch to next tab

gT

Switch to prev tab

gqq

Format line

gq

Format lines

q. / q

Begin/ finish recording macro using the named macro register.

Supported motions

h

Left

<left>

Left

<backspace>

Left

j

Down

<down>

Down

<enter>

Down to first non blank

k

Up

<up>

Up

–

Up to first non blank

l

Right

<right>

Right

<space>

Right

$

To EOL

<end>

To EOL

0

To 0 column

<home>

To 0 column

^

To first character of line

f.

Find char

F.

Find char backward

t.

To char

T.

To char backward

;

Repeat last t. or f. command

,

Repeat last t. or f. command

n

Find next

N

Find prev

gg

To first line

G

To last line

w

Word forward

W

WORD forward

b

Word backward

B

WORD backward

e

To end of word

E

To end of WORD

ge

To end of prev word

gE

To end of prev WORD

|

To screen column

%

To matching item

`[a-zA-Z><]

To mark

‘[a-zA-Z><]

To mark line

[[

To previous brace block start

]]

To next brace block start

[]

To previous brace block end

][

To next brace block end

*

To next occurrence of word under cursor

#

To prev occurrence of word under cursor

H

To first line of window

M

To middle line of window

L

To last line of window

gj

To next visual line

gk

To prev visual line

Supported text objects

iw

Inner word

aw

A word

iW

Inner WORD

aW

A WORD

i”

Inner double quote

a”

A double quote

i’

Inner single quote

a’

A single quote

i`

Inner back quote

a`

A back quote

ib

Inner paren

i)

Inner paren

i(

Inner paren

ab

A paren

a)

A paren

a(

A paren

iB

Inner curly bracket

o}

Inner curly bracket

i{

Inner curly bracket

aB

A curly bracket

a}

A curly bracket

a{

A curly bracket

i<

Inner inequality sign

i>

Inner inequality sign

a<

A inequality sign

a>

A inequality sign

i[

Inner bracket

I]

Inner bracket

a[

A bracket

a]

A bracket

i,

Inner comma

a,

A comma

Supported insert mode commands

<c-d>

Unindent

<c-t>

Indent

<c-e>

Insert from below

<c-y>

Insert from above

<c-w>

Delete word

<c-r>.

Insert content of register

<c-o>

Switch to normal mode for one command

<c-a>

Increase number under cursor

<c-x>

Decrease number under cursor

The Comma Text Object

This is something that I have been missing in Vim. The comma text object makes it easy to modify parameter lists in C-like languages and other comma separated lists. It is basically the area between two commas or between a comma and a bracket. In the line shown in the illustration to the right, the three ranges this text object can span are highlighted in red.

Comma text object ranges. If the cursor is over, say, “arg2”, pressing c i , (“change inner comma”) would delete “double arg2” and place the cursor between the two commas in insert mode. A very convenient way to change a function’s parameters.

Emulated Vim Command Bar

Kate 4.11 introduced a hidden config option that make “/”, “?” and “:” bring up a new search/ command in place of the usual Kate Find/ Replace / Command-line bar. The bar is intended to intended to replicate many of the features of Vim’s command bar, and also to fix many of the issues with Kate Vim mode’s interaction with Kate’s Find/ Replace bar (interactive replace not working; incremental search not positioning the cursor correctly; not usable in mappings/ macros; etc).

The following shortcuts are provided by the emulated command bar; as with Vim, these can be remapped with cmap, cnoremap, etc:

Kate Vim Extension. In a sed-replace expression (i.e. one of the form s/find/replace/[g][c][i]), clear the “find” term and place the cursor there.

<c-f>

Kate Vim Extension. In a sed-replace expression (i.e. one of the form s/find/replace/[g][c][i]), clear the “replace” term and place the cursor there.

<c-g>.

Kate Vim Extension. As with <c-r>., insert the content of the named register, but escape it in such a way that when used with a search, we search for the literal content of the register; not the content of the register interpreted as a regex.

The “context-specific completion” is decided as follows:

In a search bar (“/” or “?”), auto-complete from search history (which includes searches initiated via “*” and “#”; searches done in sed-replace expressions; etc.)

In an empty command bar (“:”), auto-complete from command history (NB: auto-completion of command names is invoked automatically when you begin typing).

In a command-bar containing a sed-replace expression (e.g. “‘<,’>s/find/replace/gc”), if the cursor is positioned over “find”, auto-complete from the “search” history; if over the “replace”, auto-complete from the history of “replace” terms.

When executing a sed-replace expression in the command bar with the “c” flag (e.g. s/find/replace/gc), a Vim-style interactive search/replace expression will be initiated.

Some example usages of the emulated command bar, with GIF animations, are given in this blog. In 4.11, the emulated command bar can be enabled by setting the hidden config option “Vi Input Mode Emulate Command Bar” to “true”. in your katerc/ kwriterc/ kdeveloprc.

Missing Features

As stated earlier, the goal of Kate’s VI Mode is not to support 100% of Vim’s features, however, there are some features which are sorely missed

The _one_ vi feature that kate that I would like to see added is the abbreviations. I.e. :ab i I or :ab tht that. I am working on a text-to-speech application for people who are mute or speech-impaired and who cannot type very fast. I have discovered that by having a standard list of roughly 130 abbrevs, typing ordinary English text can be speeded up by about 31%.

I have been a programmer for many years and am willing to add this feature–or at least help with it.

@alphi: There is experimental support for :nn[oremap] (normal mode remappings) for the Vi Mode. These are saved in ~/.kde/share/config/katerc. It should be possible to write a short script to convert from Vim’s format to the format used in the katerc file for normal mode mappings.

@alphi: Ah. Ok. Ironically Qt Creator’s “fake vim” does not support many (or any at all?) vim functionality, but just Vi functions, while Kate’s “Vi mode” support a lot of Vim functionality like text objects (I could never live without them!). 🙂

I am experimenting with Kate’s Vi Mode, but I was stuck after my first :split! I could not close the split windows! In Vim, that would be a simple :q, but Kate closes __files__ (buffers?) with :q, not split windows…

So what’s the command for closing split windows? I have tried :q, :close, C-w c, and right-clicking everywhere…

Sorry, I don’t really have the programming experience (yet) to contribute, but can we get *zt* for make current line the top line and *zb* for make the current line the bottom line? It doesn’t seem like this is the right place to make feature requests, but I don’t know where to properly make the request.

I just started using kate (because it has vi mode), but I cannot figure out how to map, for example, ALT-n to :bn and :bp
Is this supported? Or, how can I switch between open files without using the mouse?

I noticed that the Vi mode’s redo/undo is completely different than Vim. But Vim’s undo/redo movement is one of its best features. Notice how redo will ensure that your cursor is at the start of the text that was just changed. This is not the case in Kate’s Vi mode.